Improvement in sound-boards for pianos



UNITED STATES PATENT OFFICE@ P. SOHULER, OF PHILADELPHIA, PENNSYLVANIA.

Specification forming part of Letters Patent No. 53,687, dated April 3, 1866.

To all whom it may concern.-

Be it known that I, P. SOHULER, ofthe city of Philadelphia, in the State ot' Pennsylvania, have invented a new and useful Improvement in Pianos; and I do hereby declare that the following is a Jfull, clear, and exact description of the construction and operation of the same, reference being had to the accompanying drawings, making a part of this specification, in which- Figure l represents the upper side ot' the sound-board ot' a piano; Fig. 2, the under side ot' the same, and showing my improvement applied thereto; and Fig. 3, a sectional side view, like letters and numbers of referenceindicating the same parts when in the different iigures.

The object of myinvention is to improve or increase the strength of the tone or sound 0f the treble strings ot' a piano; and it consists in a rigidly-fixed application of a metallic plate to the under side of the sound-board, constructed so that it shall correspond in position, curve, and length with the treble p ortion of the usual wooden bridge on the upper side of the said board, substantially as hereinafter described.

In the drawings, A B is the sound-board; O, the treble and tenor bridges; D D, the bass bridges, and E the metallic plate applied to the under side of the board.

The plate E may be made of any suitable metal-as brass, iron, or steel; but the latter is believed to be the best-and of such a length and curve as will cause it to correspond with the length and curve of the treble portion c of the bridge O when the plate is applied to the under side of the board and directly beneath the said portion of the bridge, as shown in Figs. 2 and 3. The plate E is, in this instance, made rectangular in its transverse section, and is diminished in thickness by regular steps l 2 3 4 as it approaches the tenor portion c2 of the bridge o', its thicker end being about three-quarters orn an inch thick, more or less, and its thinner end about oneli'ourth of that thickness, the object being to gradually diminish its rigidity as it approaches the tenor portion ot' the bridge above it. It is rigidly xed to the under side of the soundboard A B in the position described and shown by means of thesorews ce, which pass through it and the stays a ofthe sound-board and into the bridge O, and thus confine it closely and rmly in contact with the said stays. (See Figs. 2 and 3.)

It will be seen that this metallic plate E will ait'ord additional strength and stiffness to the treble portion of the bridge C, without affecting unfavorably the tenor portion. I find that it causes a very great improvement in the strength of the tone or sound of the treble strings ot' the piano.

Having thus fully described my improvement in pianos, what I claim as new therein,

ot' my invention, and desire to secure by Letters Patent, is-

The application of a metallic plate, E, constructed substantially as described, to the under side and directly beneath the treble portion of the bridge O ot' the sound-board of a piano, substantially as and for the purpose described.

P. SOHULER.

Vitnesses:

BENJ. MoRrsoN, JOHN WHITE. 

